GDN (stands for Google Display Network) is part of the Google Ads ad ecosystem that allows you to run ads on websites such as blogs, news websites, and even Google’s own YouTube (on desktop).
There are a few ad sizes that you can choose from. Here are the sizes that work best:
The best and most commonly used GDN banner size is 300 x 250 pixels (source).
Here’s a sample of results based on our own research, based on a percentage of total clicks:
- 300 x 250 = 73% of total clicks
- 240 x 400 = 13% of total clicks
- 728 x 90 = 7% of total clicks
- 160 x 600 = 6% of total clicks
- 468 x 60 = 1% of total clicks
As for the share of impressions (ad views), here are the sizes that show most often:
- 300 x 250 = 62% of total views
- 240 x 400 = 13% of total views
- 728 x 90 = 17% of total views
- 160 x 600 = 7% of total views
- 468 x 60 = 1% of total views
This applies to both mobile and desktop resolutions.
The percentages are estimates and fluctuate according to market conditions. However, from our experience, square ads usually perform best.
Note: The 728 x 90 ad size has a high amount of views because it usually shows up above the fold (you’ll see it as soon as you open the page), but is often ignored and results in a lowered amount of clicks.
The reason why 300 x 250 pixels ad size works best
There are a few aspects of GDN ads to consider:
- Ad objective (views or clicks or sales/leads?)
- Mobile responsiveness (mobile or desktop-focused?)
- Web experience (ad disruption)
Modern websites are now mobile-responsive, which means they adapt their web content according to the size of the device.
Google has also updated its system to allow all websites that use GDN to automatically fit ads based on the display space available (source).
That means websites can now accommodate almost all ad sizes.
This is great for advertisers that want to remain consistent to have the same content across all platforms as well.
Social media websites, such as Facebook and Instagram, allow square ads to be placed. Your potential customers can get a familiar ad experience across all media.
The 250 x 250 pixels square ad size that was just recently introduced can allow your GDN ads to be consistent on websites now too. Just note the lowered resolution can cause smaller words to look blurry.
A better experience equals better traffic quality, and consequently better sales and leads results.
GDN mobile & desktop traffic considerations
Mobile traffic has overtaken desktop traffic a few years back.
From our internal tests, here’s where most of the traffic is coming from:
- Mobile = 95%
- Desktop PC = 4%
- Tablets = 1%
- TV = 0.01%~
Mobile traffic accounts for most of the traffic, with PC coming in at 4% and tablets at 1%. TV screens may show ads but it’s negligible.
So the question is does 300 x 250 pixels ads work on mobile too? Isn’t it too large?
There’s actually a smaller ad size that can best the 300 x 250 pixels size ad, and it’s the 300 x 50 pixels size ad.
However, even though the mobile 300 x 50 pixels ad size works great, it’s too small to include any detailed info in the ad.
Here’s an example of the ad space that’s been reduced:
It doesn’t help that you are getting ad views, but you don’t have enough space to put your ad message.
It also works similarly to the 728 x 90 pixels ad size, because it usually shows up above the fold.
Therefore, it’s only recommended if you want more ad views and not interactions.
On the other hand, large GDN ad sizes don’t work because it takes up too much screen real estate. It doesn’t provide an ideal ad experience on mobile devices.
Website owners can also choose not to allow large ads to show on mobile as it’s disruptive to their web experience, driving people away from the website.
Creating larger sizes will also require more ad production resources, and it doesn’t justify the returns for everyone involved.
The best size for GDN is 300 x 250 pixels on both mobile and desktop platforms from looking at the clicks and view rate.
Larger GDN ad sizes won’t get much reach and is disruptive to the web experience; while smaller GDN ad sizes won’t allow ads to contain any meaningful detail even though there may be views.
300 x 250 pixels ad size is the sweet spot, along with other square ad sizes.